package com.caigou.filters;

import java.io.IOException;  
import javax.servlet.Filter;  
import javax.servlet.FilterChain;  
import javax.servlet.FilterConfig;  
import javax.servlet.ServletException;  
import javax.servlet.ServletRequest;  
import javax.servlet.ServletResponse;  
import javax.servlet.http.HttpServletRequest;  
import javax.servlet.http.HttpServletRequestWrapper;  
public class TomcatFormFilter implements Filter {  
/** 
* Request.java 
* 对 HttpServletRequestWrapper 进行扩充, 不影响原来的功能并能提供所 
有的 HttpServletRequest 
* 接口中的功能. 它可以统一的对 Tomcat 默认设置下的中文问题进行解决而只 
需要用新的 Request 对象替换页面中的 
* request 对象即可. 
*/  
class Request extends HttpServletRequestWrapper  
{  
public Request(HttpServletRequest request) {  
super(request);  
}  
/** 
* 转换由表单读取的数据的内码. 
* 从 ISO 字符转到 GBK. 
*/  
public String toChi(String input) {  
try {  
byte[] bytes = input.getBytes("ISO8859-1");  
return new String(bytes, "UTF-8");  
}  
catch (Exception ex) {  
}  
return null;  
}  
/** 
* Return the HttpServletRequest holded by this object. 
*/  
private HttpServletRequest getHttpServletRequest()  
{  
return (HttpServletRequest)super.getRequest();  
}  
/** 
* 读取参数 -- 修正了中文问题. 
*/  
public String getParameter(String name)  
{  
return  
toChi(getHttpServletRequest().getParameter(name));  
}  
/** 
* 读取参数列表 - 修正了中文问题. 
*/  
public String[] getParameterValues(String name)  
{  
String values[] =  
getHttpServletRequest().getParameterValues(name);  
if (values != null) {  
for (int i = 0; i < values.length; i++) {  
values[i] = toChi(values[i]);  
}  
}  
return values;  
}  
}  
public void destroy() {  
}  
public void doFilter(ServletRequest request, ServletResponse  
response,  
FilterChain chain) throws IOException, ServletException {  
HttpServletRequest httpreq = (HttpServletRequest)request;  
if(httpreq.getMethod().equals("POST")) {  
request.setCharacterEncoding("UTF-8");  
} else {  
request = new Request(httpreq);  
}  
chain.doFilter(request, response);  
}  
public void init(FilterConfig filterConfig) throws  
ServletException {  
}  
}  
  